More than a third of us own a smartphone and, on average, will look at it a barely believable 150 times a day.

But have you ever considered what this is doing to your health? Here, we reveal how our favourite gadget can damage our bodies.

Not so good: Your mobile could be behind that outbreak of spots and can also give you a saggy jaw

RUINING YOUR EYES

If your eyes feel sore after staring at your phone, you won’t be surprised to learn that focusing on a small object for a long time can cause dry eyes, which can lead to inflammation and infection.

Even more worryingly, phones could be affecting children’s eyesight in the long-term. Mr Allon Barsam, a consultant opthalmic surgeon at Luton & Dunstable University Hospital, says it is possible that youngsters who stare at screens all day could be near-sighted as they grow up.

There’s also research to suggest that using smartphones could leave us needing glasses sooner. ‘Presbyopia, or the inability to focus on close objects, usually develops in your mid-to-late-40s, which is why everyone after a certain age needs reading glasses,’ says Mr Barsam.

'People only notice this when they can’t read a newspaper, but we tend to hold phones far closer to our eyes than papers — around 10in away as opposed to 16in — so it’s becoming a problem sooner.'

While smartphones aren’t necessarily damaging our eyes, they are demanding more of them.

'We are expected to focus at three different distances — long distance, on a newspaper or book, and on smartphones. So this could mean more than one pair of reading glasses or more expensive varifocals,' says Mr Barsam.

Unhealthy: Other problems associated with smartphone use include strained eyes and a squashed spine

The solution: Enlarge the size of the text on your phone, and to avoid glare, try to use your phone in a well-lit room and don’t use it for more than 15 minutes at a time.

Finally, as screen time has already been linked to a number of health problems in children aside from vision, including obesity and heart problems, restrict it.

Psychologist Dr Aric Sigman recommends you do not allow children aged three to seven to play games on a small screen for more than half an hour a day. This rises to up to two hours for those over 16.

SQUASHING THE SPINE

Our smartphones are changing our posture. 'Our bodies are a product of what we do on a daily basis,' says Kirsten Lord, a chartered physiotherapist.

'I now see far more people with pain in their neck or shoulders. We tend to poke our heads forward when we’re reading something on a phone or tablet. This position squashes the top of your spine and compresses the nerves that go up to your head. The result can be headaches and feeling tired and stiff.'

The solution: Invest in a hands-free kit. Kirsten also advises trying exercises to lengthen your neck muscles, such as imagining a string pulling you up from the middle of your head to help you improve your posture.

GIVING YOU SAGGY JOWLS

Excessive phone use could change the definition of your jawline. ‘I’ve seen an increase in the number of women in their 30s concerned about weakness in the lower third of their face,’ says cosmetic dermatologist, Dr Sam Bunting.

'As we age, our skin’s elasticity decreases and it’s feasible that bending our neck forward for hours on end to look at smartphones and tablets may mean there is more of a downwards tug on the delicate skin.'

The solution: Try holding your phone or tablet straight out in front of you, rather than below chest level, so you’re not constantly looking downwards.

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Deafness: Listening to music using low quality tinny sounding speakers could lead to hearing loss

CAUSING SPOTS

Considering how hot phone screens get after a long call, it’s no surprise that some experts are concerned they can give you pimples or sweat rash.

Which? magazine carried out tests on a sample of 30 mobile phones and discovered that, on average, a handset had 18 times more harmful germs on it than the flush handle in a men’s lavatory.

The solution: If you’re prone to spots, use a hands-free kit and wipe your phone with a saline solution.

DAMAGING YOUR HEARING

'Playing music through headphones too loud can cause noise-induced hearing loss (NIHL), which can make it difficult to hear speech, especially when there’s background noise,' says Karen Finch, of the Hearing Care Centre in Ipswich.

She adds: 'Many standard-issue headphones don’t fit the ear properly resulting in a leakage of sound, so we feel we have to turn up the volume.

The solution: Bespoke headphones, but even then, always keep sound levels as low as you can and don’t listen for too long.

STOPPING YOU SLEEPING

Computers, laptops, tablets and phones tend to give off a blue light, thought to interfere with the natural hormones, such as melatonin, which help us to sleep.

The solution: Research from the Mayo Clinic in Arizona suggests that dimming the brightness settings on your phone and holding it at least 14in from your face while using it will reduce its potential to impede sleep. Better yet, buy an old-fashioned alarm clock and leave your phone outside your bedroom at night.

RUINING RELATIONSHIPS

We might think our phones facilitate communication, but studies suggest otherwise. 'Technology can make it hard to manage boundaries in our lives,' says Dr Emma Short, a psychologist at the University of Bedfordshire.

'So if we’re on our phone, we don’t give our full attention to those we’re physically with.Research also suggests the more engaged we are in social networks, such as Facebook and Twitter, the more lonely we can become as family, friends and work relationships suffer.'

The solution: Have a strict rule that there are no phones at the dinner table or when you’re out socially.